Fizzypop said: Wait, don't the Puella Magi count as undead themselves?
Irony much?
They are neither dead or alive, their soul is within the soul gem. They are close to the concept of a Lich, a person whose soul is kept close to their body. Ironically enough, their weakness is close to that of a lich as well: remove the item containing their soul, and you kill the lich
